This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | -12 |
| 3 | 24 |
| 4 | 0 |
| 5 | -51 |
| 6 | 0 |
| 7 | 262 |
| 8 | -126 |
| 9 | 0 |
| 10 | -1684 |
| 11 | -47 |
| 12 | 0 |
| 13 | 480 |
| 14 | 0 |
| 15 | -854 |
| 16 | 4349 |
| 17 | 0 |
| 18 | -2690 |
| 19 | 10595 |
| 20 | 0 |
| 21 | 9074 |
| 22 | 9680 |
| 23 | 37734 |
| 24 | -48262 |
| 25 | 1200 |
| 26 | -98037 |
| 27 | 415504 |
| 28 | -1687656 |
| 29 | -1840201 |
| 30 | 2208435 |
| 31 | -24907680 |
| 32 | -20571545 |
| 33 | -2873052 |
| 34 | 23511040 |
| 35 | 255110496 |
| 36 | 98995966 |
| 37 | -17722962796 |
| 38 | 3495484872 |